Micrometer height gauge



A. w JARosz MICROMETLEIR HEIGHT GAUGE March 21, 1944.l

Filed dan: 23) 1943 Patented Mar. 21, 1944 UNITED STATES PATENT .OFFICE`assists MlCROMETER HEIGHT GAUGE Albert W. Jarosz, Detroit, Mich.Application January 23, 1943, Serial No. 473,412 2 Claims. (Q1. 33 -1,64)

Ba,sinnlichY myinvention pertains to that eless of: gauges which, areexemplified by the conventional' micrometer and in which. a screw with.e number of' threads to. a measuring unitl is used in Genn binetion withe. cylindrical thimele provided with calibrations on; its circumferenceThe purpose ofl my invention is to provide e micrometer height gauge ofsimple construction and capable of beine rnafle ata relatively low oost.f

and Yet. ntliiding. means to adjust. said gauge for accuracy wheneverneeded..

A sneoio purpose of. my intention is to. nrovide a micrometery gauge inwhich the thirnble which. is ordinarily secured to the screw forming en4essential element of the sance and turning with it, may be rotatablyadjusted with respect to seid screw, to compensate for weer of parts orto prevent any inaccuracy in eieotiris measurements with the aid of mygauge.

Another purpose of gauge is te provide means. of seeurine to itseriloers or other instruments as needed.

This and other features of my construction, will now be described indetail with reference to the accompanying drawing in which:

Fig. l is a vertical sectional view of my gauge;

Fig. 2 is a side elevation of my gauge;

Fig. 3 is a vertical sectional view of my gauge, including novel meansof locking the gauge at a definite setting;

Fig. 4 is a plan view of my gauge shown in Fig. 3;

Fig. 5 is a fragmentary sectional View of my gauge, taken on line 5 5 inFig. 3.

Similar numerals refer to similar parts throughout the several views.

The micrometer height gauge of my construction includes a cylindricalbarrel lil, resting on a broad, circular base l I. A screw-threadedspindle r micrometer screw l2, provided with a predetermined number ofthreads to an inch or other measuring unit, is disposed axially withinsaid barrel, which acts as a nut for said screw. At its upper end thescrew iiares out to form an in- Verted truncated cone I3, the base ofwhich serves as a support for a thimble I?. Projecting axially from theupper surface, that is the base of cone I3, is a short stem i which isthreaded on its outer surface. The stern passes through a smooth-boreaperture i4 in the flat top of thimble Il. A plate I8 provided with athreaded aperture, centrally located therein, is screwed upon said steml5 and above said top of thimble Il.

I wish to point out at this juncture that thimble l1 which skirts barrell0 and is in a sliding contact with the` outer surteoe. thereof, niet'be freelr rotated on its supporting @one lol-f uri-til. ele-Innen in exed. position between seid eene '3 and plete it, when the letter isscrewed. tient into a trietionel eonteot with. the upper surface ef seidtnimble in order that tine micrometersorew l2 tney turned down. to itsinvii extent. the top ofl terre! ID is counter-sunk to form a recessi9.. correspondins to the outline of oone lltV Micrometer screw I-Z isbored axially right` through from one end to the other, and is providedwith an internal thread at each end. As it may be desirable to loci; thescrew in a selected positionv against any longitudinal movement withinbarrel l 0, this may be eiected quite. simply by means or a taperedscrew 2|,l fitted axially into the lower end ofthe micrometer. screw l2,as shown in Fig. 1. Said lower end of screw i2 is split by a pluralityof radial slots 2,2. As screw 2| is turned in, it brings about anexpansion of the circumference of the lower end of the micrometer screwl2 into an increased f rictional Contact with the inner surface ofbarrel tend prevent` ing a rotary movement of said screw.

As indicated above, the hole which runs axially through the length ofscrew I2, and is identied in Fig. 1 by numeral 23, is threadedinternally at its upper end, forming a socket I6 in stem l5. This willlbe found useful in afxing a scriber or some other marking deince at thetop of my gauge, as it may be easily done by means of a screw like screw31 fitting into a sirnilal1 socket at the upper end of hole 38 in thegauge shown in Fig. 3.

Novel and more convenient means to lock the micrometer screw seatedwithin the barrel are shown in Fig. 3. In this case the thimble andparts above said thimble are identical with those shown in Figs. 1 and2. Other parts are essentially similar, as they include a base 26, abarrel 25, a micrometer screw 21 with a flared up top te, tting into acountersunk recess 24 in the top of barrel 25. However, the means tolock the micrometer screw 21 against rotation, and what follows, againstits axial movement, are diierent. The barrel, as shown in Fig. 3,contains a perpendicular cylindrical hole 30, running parallel to theinner bore of barrel 25. Disposed within the well is a rod 29, havingconical ends at the top and at the bottom respectively. The lower end ofthe rod is in contact with an adjusting screw 3i, which is threaded intothe side of the barrel so as to project into hole 30. The end of theadjusting screw within the well is tapered to abut the side of the coneon the lower end of rod 29.

At its upper end, said'rod 29 bears against a movable wedge 32, locatedwithin a horizontal slot, somewhat below the upper surface of barrel 25.When the adjusting screw 3l is turned in, it causes said rod 29 to shiftupwardly. As a result thereof, the upper end of the rod, bearing againstwedge 32, causes said wedge to move outwardly, that is radially withrespect to barrel 25, into a frictional engagement with the innersurface of thimble Il. As the thimble is connected, through intermediatemeans, with screw 21, said wedge 32 serves as a means of locking saidscrew against axial movement, as above stated.

In conclusion of my description, I wish to add that base H in Fig. 1contains on its bottom side a recess 33, and that base 26 in Fig. 3contains a similar recess 34, each recess serving to facilitate accessto the micrometer screw within the barrel rising from its respectivebase. I also wish to point out that both the barrel and the thimble ofmy gauge have suitable calibrations marked thereon, which may run fromzero upwards. Said calibrations are shown in Fig. 1 being indicated bynumerals 35 and 36, respectively. When the zero calibration on thethimble coincides with the zero calibration onY the barrel, the topsurface of my gauge is at a level which is intended to be at a certaindefinite distance from the bottom surface of said gauge. It is obvious,however, that owing to the wear of the thread of the micrometer screw,or to the wear of the top surface of my gauge or its bottom surface, theactual distance between said surfaces may become smaller to the extentof such wear. When this occurs the gauge may be returned to its initialefficiency and correctness in the following manner: The top plate I8 isloosened, to permit free rotation of thimble I1 while the micrometerscrew remains stationary; the thimble thereupon is turned on itssupporting cone to the extent necessary to compensate for said wear, andthe top plate is again tightened so that the thimble and the micrometerscrew turn together. The rotary adjustment of the thimble ought to besuch that the initial distance between the top and the bottom surfacesof my gauge will be true and accurate when the zero calibration on thethimble will coincide with the zero calibration on the barrel.

Having thus described my improvement, I wish to claim the following:

1. In a micrometer height gauge, comprising an upright calibratedbarrel, a micrometer screw, axially disposed within said barrel, and anexternally calibrated thimble, rotating with said screw and skirting theouter surface of the barrel, in combination, a cylindrical hole in therim of the barrel, running downwardly parallel to its aXis, alongitudinal rod within said hole, having cone-shaped ends at the topand at the bottom respectively, an adjusting screw laterally thread.- edinto the wall of the barrel, the end of said screw being in form of acone and abutting the lower end of said rod, and a wedge in the wall ofthe barrel, close to its top, in a horizontal slot therein, said wedgebeing in abutment with the cone-shaped upper end of the rod, andradially movable by said upper end of the rod against the inner surfaceof the thimble into a frictionally binding contact therewith.

2. In a micrometer gauge of the kind described, and including a barreland a rotatable thimble skirting it, means to lock the thimble againstrotation, comprising, a hole in the rim of the barrel parallel to itsaxis, a rod in the hole, having both ends cone-shaped, a slot in thewall of the barrel opposite the upper end of the rod, a Wedge in theslot bearing against the cone-shaped, upper end of the rod, and screwmeans abutting the cone-shaped lower end of the rod to push the rodupwardly against the side of the wedge to move it outwardly, out of theslot into a frictionally binding engagement with the inner surface ofthe thimble.

ALBERT W. JAROSZ.

